Department of Biomedical Engineering, Florida International University, Miami, FL, United States of America.
School of Biological & Health Systems Engineering, Arizona State University, Tempe, AZ, United States of America.
PLoS One. 2019 Jan 16;14(1):e0210956. doi: 10.1371/journal.pone.0210956. eCollection 2019.
Current myoelectric prosthetic limbs are limited in their ability to provide direct sensory feedback to users, which increases attentional demands and reliance on visual cues. Vibrotactile sensory substitution (VSS), which can be used to provide sensory feedback in a non-invasive manner has demonstrated some improvement in myoelectric hand control. In this work, we developed and tested two VSS configurations: one with a single burst-rate modulated actuator and another with a spatially distributed array of five coin tactors. We performed a direct comparative assessment of these two VSS configurations with able-bodied subjects to investigate sensory perception, myoelectric control of grasp force and hand aperture with a prosthesis, and the effects of interface compliance. Six subjects completed a sensory perception experiment under a stimulation only paradigm; sixteen subjects completed experiments to compare VSS performance on perception and graded myoelectric control during grasp force and hand aperture tasks; and ten subjects completed experiments to investigate the effect of mechanical compliance of the myoelectric hand on the ability to control grasp force. Results indicated that sensory perception of vibrotactile feedback was not different for the two VSS configurations in the absence of active myoelectric control, but it was better with feedback from the coin tactor array than with the single actuator during myoelectric control of grasp force. Graded myoelectric control of grasp force and hand aperture was better with feedback from the coin tactor array than with the single actuator, and myoelectric control of grasp force was improved with a compliant grasp interface. Further investigations with VSS should focus on the use of coin tactor arrays by subjects with amputation in real-world settings and on improving control of grasp force by increasing the mechanical compliance of the hand.
目前的肌电假肢在为用户提供直接感觉反馈方面的能力有限，这增加了注意力的需求并依赖视觉线索。振动触觉替代 (VSS) 可以以非侵入性的方式提供感觉反馈，已证明在手部肌电控制方面有一定的改善。在这项工作中，我们开发并测试了两种 VSS 配置：一种是带有单个突发率调制致动器，另一种是带有五个硬币触觉器的空间分布式阵列。我们对这两种 VSS 配置进行了直接比较评估，以调查有能力的受试者的感觉感知、肌电控制抓握力和手张开度以及界面顺应性的影响。六名受试者在仅刺激的范式下完成了一项感觉感知实验；十六名受试者完成了实验，比较了在抓握力和手张开度任务中进行感知和分级肌电控制时两种 VSS 配置的性能；十名受试者完成了实验，研究了肌电手的机械顺应性对手部抓握力控制能力的影响。结果表明，在没有主动肌电控制的情况下，两种 VSS 配置的振动触觉反馈感觉感知没有差异，但在肌电控制抓握力时，硬币触觉器阵列的反馈要好于单个致动器。在硬币触觉器阵列的反馈下，抓握力和手张开度的分级肌电控制要好于单个致动器，并且具有顺应性抓握接口可以改善抓握力的肌电控制。进一步的 VSS 研究应集中在有截肢的受试者在实际环境中使用硬币触觉器阵列以及通过增加手的机械顺应性来改善抓握力控制。
